no shift cable tension [archive]

LewisBricktop

about halfway through a 40 mile ride today, after all was going well, i went to shift on the cassette and nothing happened. the chain and derailleur are stuck on the 12t cog and there is very little tension in the cable throughout, at least where it isnt in the housing and i can see it. i looked in the lever itself which is an '07 105 model, and the cable appears to be pulling appropriately as i use the lever (away from the bike as i downshift, and vice-versa). i dont know much about shifting mechanisms yet so im stuck. could the cable just be shot? is replacement something i could do easily? parktool's explanation for replacement didnt seem very helpful.

daveornee

about halfway through a 40 mile ride today, after all was going well, i went to shift on the cassette and nothing happened. the chain and derailleur are stuck on the 12t cog and there is very little tension in the cable throughout, at least where it isnt in the housing and i can see it. i looked in the lever itself which is an '07 105 model, and the cable appears to be pulling appropriately as i use the lever (away from the bike as i downshift, and vice-versa). i dont know much about shifting mechanisms yet so im stuck. could the cable just be shot? is replacement something i could do easily? parktool's explanation for replacement didnt seem very helpful.
Are the cable housing ends properly seated in the frame stops?
If you pull the cable by hand, at the right rear of the bicycle by the chain stay, does the RD move?

LewisBricktop

the housing ends appear to be fine, HOWEVER...

when i pull the cable by the stay, the RD does not move and the cable just seems to stretch leaving it essentially dangling from the bottom of the bike.

kdelong

Inspect your cable housings for splits or damage from the inside out. This same thing happened to me on my front derailer. It's a long, slow ride home when you only have the lower range of gears available. I was able to work on my cadence though:D. The ironic thing is that I always carry a spare cable but never a cable housing.

531Aussie

the housing ends appear to be fine, HOWEVER...

when i pull the cable by the stay, the RD does not move and the cable just seems to stretch leaving it essentially dangling from the bottom of the bike.Sounds like the allen wrench cable clamp on the rear derailleur is loose, and the cable is pulling through it. If so, after pulling it through and reclamping, it's likely you'll have to have the gears adjusted again.

Make sure the cable is properly seated in the gear lever, and that the lever is in the "clicked all the way out" position

Be careful tightening the cable clamp on the rear derailleur; they don't need a lot of tension, and it's possible to thread or bust something (I once did it years ago :()

I'm not big on carrying a heap of tools on a ride, but I always have a 5mm and 4mm allen key in my pocket, because they cover about 20 or 30 bolts on a bike

gclark8

all good advice above.

If still in doubt, fit a new inner cable, they cost about $1. ;)

531Aussie

If still in doubt, fit a new inner cable, they cost about $1. ;)
better yet, get a stainless steel one for $3 :)

sogood

Even better, get to know the following two web sites.

http://www.sheldonbrown.com/

http://www.parktool.com/repair/